The zero-cost gate showed every benchmark executable changing: the new string literals and floating-point constants grew the merged constant pools of scr_json.o and scr_lib.o, which every program linking those units carries, and edits to scr_dyn_fn_get and scr_dyn_has_own changed code the typed benchmarks reach. - The builtin constructor values, the inherited Object.prototype members and the stored timer functions move to scr_dyn_invoke.c, which links only into programs that use them: the frontend now selects that unit for dyn.globalConstructor, dyn.builtinFunction, dyn.objectTag and constant-key reads of constructor/valueOf/toString/hasOwnProperty/ propertyIsEnumerable. Those reads call scr_dyn_inherited_read after the ordinary read (and scr_dyn_object_prototype_member before it, since the ordinary read fences Object.prototype itself); computed-key reads keep their old answer. The unit's new strings live in their own section so programs linking it for other reasons keep their bytes. - scr_date_parse_get_time keeps its exact body; Date.parse and new Date(string) call the new scr_date_parse (bounded grammars, then V8's parser), and JavaScript `new Date(value)` calls scr_dyn_native_date_new_value, so fs.Stats dates are untouched. The parser and UTC(t) avoid new pooled constants. - Object.prototype.toString's "[object Error]" moves to scr_dyn_object_tag_of; scr_json.c is unchanged. - Calling or constructing through stored constructor values and own-property checks on Object.prototype itself are not supported in this change (they would touch shared code). Also pins the IMF-fixdate (cookie Expires) parse and Date#toUTCString round-trip in the corpus. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
scriptc
scriptc compiles TypeScript and JavaScript to native executables and WebAssembly. It uses the types checked by the TypeScript compiler to generate machine code, and the output runs without Node.js installed. npm packages your program imports compile along with it. Code scriptc can't compile is reported at build time with a diagnostic and, where available, a rewrite hint.
scriptc is experimental and supports a subset of JavaScript, TypeScript, and Node.js APIs. Run scriptc coverage on an existing program to see how much of it compiles, and see the limitations and Node.js compatibility reference for details.
Installation
Install with Node.js 24 or later and npm:
$ npm install -g scriptc
The installed compiler runs natively on macOS, Linux, and Windows. Node.js is needed only to install it and to run WASI modules with scriptc run. Standalone compiler archives are also available from GitHub Releases.
Building executables requires a linker and the platform SDK or sysroot. See the quickstart for prerequisites and platform support for host requirements, cross-compilation, and WebAssembly.
Build a program
Create hello.ts:
const who = process.argv.length > 2 ? process.argv[2] : "world";
console.log(`hello, ${who}`);
scriptc run compiles the file and runs the result:
$ scriptc run hello.ts
hello, world
scriptc build writes an executable:
$ scriptc build hello.ts -o hello >/dev/null
$ ./hello scriptc
hello, scriptc
These examples use POSIX shell syntax. On Windows, build hello.exe and run it with .\hello.exe.
Use scriptc coverage hello.ts to check what compiles before you build. See coverage reports for details.
Use Node APIs
Supported Node APIs compile to the native runtime. For example, server.ts:
import { createServer } from "node:http";
const server = createServer((req, res) => {
res.setHeader("content-type", "application/json");
res.end(JSON.stringify({ path: req.url }));
});
server.listen(8080, () => {
console.log("listening on http://localhost:8080");
});
$ scriptc build server.ts -o server >/dev/null
$ ./server
listening on http://localhost:8080
Use npm packages
npm packages compile into the executable with your code, so it doesn't read node_modules at runtime.
Create cli.ts:
import pc from "picocolors";
console.log(pc.green("hello from scriptc"));
$ npm install picocolors
$ scriptc build cli.ts -o cli >/dev/null
$ ./cli
hello from scriptc
Package support is partial. See npm dependencies for which packages compile and how to check them.
Documentation
- Introduction: what scriptc is and what you can build.
- Quickstart: installation and your first executable.
- Coverage reports: check whether an existing program compiles.
- Platform support: cross-compilation and WebAssembly.
- CLI reference: commands, options, and output formats.
- Native program objects: use compiler output in external builds.
- Native FFI: call C ABI functions from compiled programs.
- WebAssembly modules: build and embed WASI modules.
- Examples: programs and integration examples in this repository.
Contributing
See CONTRIBUTING.md for source setup, testing, native artifact builds, and docs development.